A characterization framework for visual languages

The general goal of this research is to facilitate the development of visual language environments for the class of visual languages that are based on graph models. The approach the authors take relies on a conceptual framework to define general model components and behaviors; any particular language is defined by selecting and enhancing components and behaviors within the framework. The objective is to provide a system, based on the conceptual framework, in which the language designer defines a data model in conjunction with a distinct, but related, representation of the model. The language specific modules of the resulting visual language system are generated from the specification. These language modules can be viewed as system independent abstract data types which are placed into a fixed system environment. This work enables the visual language developer to easily experiment with different aspects of a visual language. It also provides a basis for the development of, and experimentation with, mechanisms used to support the use of complex visual languages and their environments. The authors address the issue of usability and language complexity by providing support for the development of mechanisms such as visual abstraction hierarchies, multiple views, multiple windows, language component filtering, etc